With the boom of science and the prevalent application of computer technologies, the information on the Internet increases rapidly. Meanwhile, the e-commerce is developed continuously and an information system of an enterprise gains more and more leverage in the competitiveness of the enterprise, so that the amount of data of the enterprise increases quickly, and the enterprise is more and more dependent on data. Storage technologies also need to be developed continuously to store a large amount of data better and more quickly.
In the conventional art, a home controller needs to be designed on a Logical Unit Number (LUN) of a cache to simplify design of the cache. In this way, a request intended for a LUN is executed on the home controller. Controller—0 and controller—1 are connected through a minor channel. The mirror channel is connected to a minor chip of controller—0 and a minor chip of controller—1 respectively. A server is connected to a Peripheral Component Interconnection Express (PCIE) interface card of controller—0 and a PCIE interface card of controller—1 respectively through a switch network. Through a hard disk extension chip, controller—0 is connected to a hard disk that provides a conventional interface; through a hard disk extension chip, controller—1 is also connected to a hard disk provided with a conventional interface. Within a controller, the hard disk extension chip is connected to a PCIE switch chip through a hard disk controller, and the PCIE switch chip is respectively connected to the PCIE interface card, the minor chips, and the hard disk controller, and is connected to a chipset and a memory through a Central Processing Unit (CPU).
When the server sends a request, the request is sent to the controller through a preferred (the shortest) path. The server determines whether the controller is a home controller. If the controller is a home controller, this controller processes the request; if the controller is not a home controller, the controller forwards the request to the home controller, and the home controller processes the request. For example, the home controller of LUN—0 is controller—0. When the server sends a request intended for LUN—0 to controller—1 through a PCIE interface card n in the preferred path, if the server determines that controller—1 is not the home controller of LUN—0, controller—1 forwards the request intended for LUN—0 to the home controller of LUN—0. That is, controller—1 forwards the request intended for LUN—0 to controller—0 through a mirror channel, and controller—0 processes the request.
In the process of implementing the present invention, the inventors find at least the following problems in the conventional art:
Controller—0 and controller—1 have a stand-alone PCIE interface card which is unavailable to a peer controller, causing resource waste. A storage controller is inaccessible to a conventional hard disk without the need of a hard disk controller or a hard disk extension chip. The use of the hard disk controller and the hard disk extension chip causes a high controller cost.